Definition
Orbital cavity surgery refers to all procedures performed on the orbitopalpebroconjunctival region with the aim of repairing the intra-orbital contents to enable the wearing of an ocular prosthesis, either because of poor contention, or because the aesthetic result is insufficient.
When should the eye be removed from its socket?
Most of the time, these are anophthalmic patients (no eyeball), the eye having been lost and/or removed as a result of trauma, burns, retinal tumor/cancer, malformation, severe glaucoma, etc.
Surgical principles and methods
The clinical examination of the environment will often need to be supplemented by a radiological work-up (CT scan, MRI). Clinical appearance varies from patient to patient, underlining the variety of non-stereotyped surgical techniques. Reconstruction of the orbital skeleton may involve the use of bone grafts harvested from the patient, or substitute biomaterials (coral, for example).
Orbit rehabilitation will involve different techniques depending on the local condition:
- Changing an undersized implant,
- Placement of a graft taken from the patient (dermo-fat graft),
- Filling using a nearby muscle (temporal),
- Placement of a volumizing product or addition of the patient’s own fat.
The space behind the eyelids, known as the conjunctival cul-de-sac, must be sufficiently deep and flexible to contain the prosthesis and allow movement. It can be reconstructed by grafting mucous membrane from the inside of the lips or cheeks, or amniotic membrane.
Eyelid reconstruction may involve the use of elements from other healthy eyelids, grafts, or neighboring elements using various plastic surgery procedures.
In cases of significant retraction, a skin graft can be used to recreate a cavity that can accept a prosthesis. The space for the prosthesis is created by means of a plastic conformer on which healing takes place. It is usual to close the eyelids by suturing them together for the duration of the healing process, i.e. for several weeks, after which they can be opened under local anaesthetic. The existence of skin in a cavity generates secretions, and requires regular care (cleaning, application of antiseptic solutions).
After six months, the patient can receive a custom-made prosthesis. Today, these prostheses closely resemble a natural eye, far from what used to be called a“glass eye“. Today’s prostheses are made of resin rather than glass. They are therefore lighter and, above all, less fragile.
Each prosthesis is made to measure. It’s all done by hand: from the shape to the tint of the white of the eye, to the most minute details, such as the red silk threads used to reproduce the blood vessels.
The prosthesis must be replaced every six years. In the meantime, it must be cleaned every day. Polishing, once or twice a year, remains the most important maintenance.
Another type of prosthesis is available for patients who have not been enucleated: a scleral lens or cover prosthesis. Very thin, it is reserved for patients in whom the eyeball has been preserved, but whose eye is unsightly or severely atrophied.